Aggregate Principal Amounts Due on Mortgage Notes Payable by Unconsolidated LLCs, Accounted Under Equity Method (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Schedule Of Equity Method Investments [Line Items]
2016		$ 13,714
2017		50,572
2018		22,837
2019	[1]	145,757
2020		1,141
2021 and After		18,385
Total		252,406
Mortgage Loan Balance		28,895	$ 52,728
Equity Method Investments
Schedule Of Equity Method Investments [Line Items]
2016		530
2017		5,727
2018		445
2019		466
2020		484
2021 and After		21,243
Total		28,895
Mortgage Loan Balance	[2]	$ 28,895	52,728
Equity Method Investments | Arlington Medical Properties
Schedule Of Equity Method Investments [Line Items]
Mortgage Loan Balance	[2],[3]		23,287
Maturity Date	[3]	2015-10
Equity Method Investments | FTX MOB Phase II
Schedule Of Equity Method Investments [Line Items]
Mortgage Loan Balance	[2]	$ 5,427	5,548
Maturity Date		2017-08
Equity Method Investments | Grayson Properties
Schedule Of Equity Method Investments [Line Items]
Mortgage Loan Balance	[2]	$ 14,670	14,893
Maturity Date		2021-09
Equity Method Investments | Brunswick Associates
Schedule Of Equity Method Investments [Line Items]
Mortgage Loan Balance	[2]	$ 8,798	$ 9,000
Maturity Date		2024-12

[1] Includes repayment of $142.2 million of outstanding borrowings under the terms of our $185 million revolving credit agreement.

[2] All mortgage loans require monthly principal payments through maturity and include a balloon principal payment upon maturity.

[3] In October, 2015, we borrowed an additional $22.8 million under our Credit Agreement to repay this outstanding third-party mortgage loan on its scheduled maturity date. These funds were advanced as a member loan to Arlington Medical Properties, LLC pursuant to a 5.29% fixed rate note with terms similar to those in place pursuant to the recently repaid third-party mortgage loan.